Modern commercial aircraft are equipped with several airplane systems to manage an aircraft's performance and to report to the pilots (flight crew) if the aircraft is not performing to the expected performance level. For example, during the landing phase of flight, a number of aircraft systems involving the aircraft's flight control, propulsion, navigation, thrust management, flight management, warning/advisory, and displays may be utilized to monitor and determine whether the aircraft's landing performance is satisfactory. However, in the end, the final determination on whether to land the aircraft or execute a go-around rests with the pilots.
The landing phase of flight is one of the most critical phases of flight. Whether a manual or automatic landing is being performed, pilots must vigilantly monitor not only the performance of airplane systems but also the progression of the landing to execute a safe landing and roll out. One characteristic of all landings is the requirement to ensure the aircraft touches down at a point on the runway such that it can decelerate and stop, or exit the runway onto a taxi way, within the runway remaining. Thus, during the landing phase of flight, pilots are focused on landing their aircraft in the touchdown zone to ensure there is enough runway for a successful deceleration and rollout.
The touchdown zone is typically the first one third of the runway with the touchdown point being the mid-point of the zone. The touchdown point in the touchdowns zone, which may be different for each landing, is affected by a number of factors including but not limited to the aircraft's weight and configuration, aircraft speed, runway head wind or tail wind component(s), weather, and runway surface conditions. Thus, on short runways, or more generally, on runways where the combination of runway length and the aircraft's landing and deceleration performance capabilities are critical, landing the aircraft as near as possible to the runway threshold is essential.
At present, pilots typically utilize landing performance data obtained from aircraft manufacturers to plan and execute landings. However, if landing conditions or the combination of landing conditions and the aircraft's capability vary such that landing performance margins are reduced, pilots have little time to abort the landing and execute a go-around. Furthermore, beyond the aircraft manufacturer's landing performance data, as well as, their own “out-the-window” visual monitoring and somewhat subjective determination, pilots have no robust system-aided feedback that gives them an indication of whether their aircraft will land at or before their desired landing point in the touchdown zone.
Thus, there is a need for a landing decision aid that will provide pilots feedback as too whether to continue the landing or execute a go-around.